RFE on the AOS stuff

Ah, delight. I've just received the following...

[me] is named on your federal tax return. We do not have evidence that she has a legal working status in the United States. That is the reason for sending Item H17 below. We do not have your supporting documents (W2s or 1099s) to determine the amount of money earned by the petitioner and by the beneficiary. If the petitioner does not meet the income requirements then it will be necessary to get a joint sponsor or evidence of your assets that are named in your I-864.

G24:The petitioner/sponsor on form I-864 must submit all supporting tax documention submitted to the IRS for the most recent year.

H3:The petitioner/sponsor indicates on I-864 that qualifying househould members' income will be used for the petitioner/sponsor's income to meet 125% of the poverty line. The petitioner/sponsor failed to submit one or more Forms I-864A for household members whose income is being used to meet the poverty line. Submit form I-864A for all household members whose income is being used.

H17:For the household member's income to be included in the household income, the household member's income must have been from a lawful source and earned while the household member was authorized to work in the United States. Submit evidence of the household member on Form I-864 or I-864A was authorized to work in the United States. Examples include [EAD, proof of Naturalization or Citizenship, etc]

I am indeed named on my husband's tax return (married filed jointly), I don't have a legal working status, and I am not and haven't been working. So I... uh... guess I can't give them half of the information they're asking for here? What do I do instead? What exactly is the I-864A, do I actually need one, and if so where can I obtain it online other than the USCIS website (the file claims to be 'damaged' and won't let me read it)?